Cod sursa(job #1136045)

Utilizator Cosmin1490Balan Radu Cosmin Cosmin1490 Data 8 martie 2014 18:24:11
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 2.28 kb
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <fstream>
#include <iterator>
#include <random>
#include <assert.h>
using namespace std;

const string file = "dijkstra";

const string infile = file + ".in";
const string outfile = file + ".out";

const int INF = 0x3f3f3f3f; 

//#define ONLINE_JUDGE

void dijkstra(int start, vector<vector<pair<int, int> > > & G, vector<int>& distance)
{
    distance[start] = 0;
    priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > heap;
    heap.push(make_pair(0, start));
    while(heap.empty() == false)
    {
        pair<int, int> c = heap.top();
        heap.pop();
        int d = c.first;
        int x = c.second;
        if(distance[x] != d)
            continue;
        for(vector<pair<int, int> >::iterator itr = G[x].begin();
                itr != G[x].end();
                itr++)
        {
            int dstNode = itr->first;
            int newDist = distance[x] + itr->second;
            if(distance[dstNode] > newDist)
            {
                distance[dstNode] = newDist;
                heap.push(make_pair(distance[dstNode], dstNode));
            }
        }
    }
}

int main()
{
#ifdef ONLINE_JUDGE
	ostream &fout = cout;
	istream &fin = cin;
#else
	fstream fin(infile.c_str(), ios::in);
	fstream fout(outfile.c_str(), ios::out);
#endif	
    int N, M;
    fin >> N >> M;

    vector<vector<pair<int, int> > >  G(N + 1);
    vector<int> distance(N + 1, INF);
    for(int i = 0; i < M; i++)
    {
        int x, y, c;
        fin >> x >> y >> c;
        G[x].push_back(make_pair(y, c));
    }

    dijkstra(1, G, distance);

    for(int i = 2; i <= N; i++)
    {
        fout << (distance[i] == INF ? 0 : distance[i]) << " ";
    }
    fout << "\n";
#ifdef ONLINE_JUDGE
#else
    fout.close();
	fin.close();
#endif
}